Google has ended support of its first-gen Chromecast dongle. These alternatives are your best bet for a replacement.
Google Chromecast Audio review
1st-Gen Chromecast Stops Receiving Major Updates
Looking back at the original Google Chromecast, which just turned 10 - The Verge
Chromecast with Google TV HD Review: Raising the Bar - CNET
Why It Might be Time to Update Your Old Chromecast
The first Chromecast is obsolete. Here's what you should get next
Chromecast with Google TV: What you need to know - Android Authority
Chromecast vs Fire Stick: Which streaming device is best for you?
20 Things You Didn't Know Your Google Chromecast Could Do
Chromecast with Google TV (HD) - Streaming Stick Entertainment on Your TV with Voice Search - Watch Movies, Shows, and Live TV in 1080p HD - Snow : Electronics
New Chromecast 4K with Google TV taking forever on initial setup : r/ Chromecast
First-gen Chromecast Still Secure, but New Features Unlikely